第6章 总复习题
The conductivity of polyacetylene drops rapidly in contact with air. There is a brighter future for intelligent devices in the home.
The scientists found that the blood vessels in the leg cannot swell.
Once upon a time, bold claims were made about computers, the future and the “paperless office”. 聚乙炔一接触空气，其导电性就迅速下降。 家庭智能装置仍有着更加光明的前景。（省译） 科学家们发现腿内的血管不会肿胀。
曾几何时，有人就有关计算机、未来和“无纸化办公”做过大胆的预测。 The doctor advised against the use of the new treatment.
If a good base cannot be found at a reasonable depth, then a so-called deep foundation must be provided.
Magnetic lines of force cannot be seen, but we know they exist by what they do. 磁力线是看不见的，但是我们按照它们的作用即知它们的存在。 医生建议不要使用新的治疗方法。
若在合理的深度内找不到坚实的地基层，那就要采用所谓的深基础。 We may process directly with Kirchoff’s voltage law for the circuit. The proper values of a and b are determined from two conditions. Optional communications are free from electromagnetic interference. This type of discrepancy could have resulted from differences in kinetics. a和b的值由两个条件决定。
对于电路，我们可直接从克希荷夫电压定律讲起。 光电通信不受电磁的干扰。
这种差异可能是由动力的不同而造成的。
The visual image of the letters making up the word is converted into its spoken equivalent. Primitive man made weapons, tools, and utensils of copper, brass, and bronze.
The longer wavelengths of radio signals pass through the atmosphere relatively undisturbed. 将组成词的各字母的视觉形象转换成该词对应的发音。 相对来说，波长较长的射电讯号通过大气时没有受到干扰。 原始人类用铜、黄铜和青铜制作成各种武器、工具和器皿。
Most hardness-testing systems employ a standard load which is applied to a ball or pyramid in contact with the material to be tested.
All metals are corrodible under the proper circumstances.
The design of the rocket nozzle also has much to do with the behavior of the exhaust and the resulting velocity of the vehicle itself.
多数的硬度实验系统使用一标准载荷加在与实验金属相接触的小球或棱锥上。 所有金属在一定情况下都是可腐蚀的。
火箭喷管的设计与排气的性能及飞行器本身的有效速度有很大关系。
Peripheral milling operations are usually performed on milling machines with the spindle positioned horizontally; however, they can also be performed with end mills on vertical-spindle machines.
Copper and aluminum are the best conductors of electric current only after silver. From various experiments we cannot but think the theory still holds good. 周铣作业通常在带有水平定位主轴的铣床上进行，但也可以在带有端面铣刀的主轴铣床上进
行。
铜和铝是仅次于银的最好的导电体。
根据各种实验，我们不得不承认这个理论依然是行之有效的。 Hydrogen is generated from zinc and sulfuric acid.
The sort of fish cannot live in the temperate zone, let alone in the frigid zone. The locomotive developed some new problems on its line-test. Gases can be chemisorbed or physically absorbed on solids. 氢由锌和硫酸所产生。
这种鱼不适合在温带生活，更不必说在寒带了。 这台机车在试运行时出现了一些新问题。 气体能化学吸附或物理吸附在固体上。
Under ideal conditions the fatigue failure will consist of a spotting of the load-carrying surfaces. Oxidation implies the combination of other elements with oxygen to form compounds. 在理想条件下，疲劳失效将是承载表面的点蚀。 氧化意味着其他元素与氧形成化合物。 7.1 连词的一般译法 第1节 翻译练习1
Carbon steel contains only iron and carbon, while alloy steel contains some other alloying metals. Because this current continually reverses in direction, it is called an alternating current. Liquid and vapor phases cannot coexist in equilibrium.
碳钢只含有铁和碳，而合金钢含有一些别的合金金属。 由于这种电流不断地改变方向，故称为交流电。 液相和气相不能在平衡中并存。 第1节 翻译练习2
Some companies replace certain parts regularly, determining the effective life of a part and then replacing it just before it would wear out.
The cost of making these tests is very low when it is divided by the total number of parts manufactured.
一些公司定期更换某些零部件，先推定零部件的有效寿命，以便在零部件即将磨损之前予以更换。
如果以生产零件的总数来划分，这些实验的成本会非常低。 Why use metal when you can use plastic?
A brief description of how transistors are manufactured is given here. That is why surfactants are so widely used in industry. 既然能用塑料为什么你却使用金属呢？ 这里对晶体管的是生产方法作一简略叙述。 这就是在工业上广泛使用表面活性剂的原因。 第1节 翻译练习3
Sometimes it is necessary to drill to a depth of 1,000 meters or more, before water is found in sufficient quantity.
It is stated that the positioning system has an accuracy of repeatability within 0.0002 inch. When short waves are sent out and meet an obstacle they are reflected. 有时必须钻到1000米或更深的深度，才能找到足够量的水。 据称，该定位系统的重复精度在0.0002英寸。
短波发送出去，遇到障碍就反射回来。 7.2 常用并列连词的译法 第2节 翻译练习1
Computers cope with negative numbers and fractions in binary arithmetic. Oxygen is chemically active and takes part in many reactions. 计算机采用二进制算法来处理负数与小数。 氧的化学性能活泼，能参与许多反应。（省译）
Modern electronic computers and other devices will be made smaller by the development of LSI. Some electrical engineers design and maintain power plants, transmission lines and home and factory electrical installations.
大规模的集成电路的发展将使现代化电子计算机以及其他装置越来越小。
有些电气工程师设计和保养发电厂、输电线、以及各种家用和工业用电器设备。 第2节 翻译练习2
The induced electromotive force lags and the current leads. Like charges repel and unlike charges attract. 感应电动势滞后，而电流导前。 同性电荷相斥，异性电荷相吸。（省译）
Transformers are commonly used in radio receivers and electrical communication circuits, and they are generally much smaller than those for power transmission.
Analyzing the dynamics of the way a person signs his or her name, and not just how the signature looks, is one basis of a biometric verifier.
变压器通常用于无线电收音机和电信电路中，可是这些变压器一般比用于输电的变压器小得多。
分析一个人签名时书法的笔力，而不只是分析签名的字形如何，这是生物统计学核实器的一个基本点。
第2节 翻译练习3
It is important to know that different types of control circuits may be used in one control system, and a completed control loop may consist of a combination of electric, pneumatic, or hydraulic elements.
重要的是要知道，在一个控制系统中可使用不同类型的控制电路，而且一个完整的控制回路可由电力、气动或液压配合组成。
The synchronous motor is even more expensive and requires a source of d.c. excitation, as well as special synchronizing control to apply the d.c. power at the correct instant. Telephone communication is now widespread and efficient. The machine is old and heavy. 同步电动机则更贵，而且需要直接励磁电源和专门的同步控制器以便在适当的瞬间接入直流电源。
现在的电话通讯既广泛又有效。 这台机器又旧又笨重。 第2节 翻译练习4
We have to replace some of its parts and make this machine more efficient.
To make the balloon descend, the “pilot” opened a valve and allowed some of the gas escape. 我们必须调换某些零件，以使这台机器效率更高。
为使气球降落，“飞行员”打开阀门，以使部分气体逸出。
Change one or more steps and we will improve the quality of the finished products.
Use a transformer and we can transform power at low voltage into power at high voltage and vice versa.
若改变一个或几个步骤，我们就有可能提高成品的质量。
用了变压器，我们就可以把低电压变为高电压，也可把高电压变为低电压。 第2节 翻译练习5
Uncap openings in indicators and connect lines.
Install aluminum washers nest to pump, steel washers next, and install nuts. Lead lacks tensile strength and it cannot be drawn out in the form of fine wire. 取下仪表开口处的盖子，再接上管路。 铅的张力差，因此不能制成细丝状。
紧贴泵处安上铝垫片，然后加钢垫片，再安上螺栓。
For LP turbine there is no residual axial thrust caused from blading because of the turbine’s double-flow arrangement of blading and thus no balancing piston is needed.
至于低压汽轮机，并没有残存的轴力，因为汽轮机的叶栅作双流配置，因而也无需采用平衡轮。
第2节 翻译练习6
The plan is very complicated technically, but the general idea is quite simple.
Now the electrons which have been driven onto the negative plate are trying to get back to the positive plate, but cannot do so because of the e.m.f which is applied to the plates. 这一计划在技术上十分复杂，但总的想法却相当简单。
现在已被赶到负极上的电子力图返回正极，可是由于极板上施加有电动势的缘故而办不到。 There are already a number of modern vehicles which are not yet in common use, but which may become a usual means of transport in the future. 现在已有一些现代化的运载工具，它们目前尚未被普遍使用，但将来可能成为一种日常的交通工具。
第2节 翻译练习7
But that he prevented me, I might have kept the machine parts in the damp place.
But that the checking up of the experimental data had taken so much time, we should have completed our work long ago.
若不是他阻止，我可能就会把那些机器零件保存在潮湿的地方。 假若检验这些实验数据不花那么多时间，我们早就完成了这项工作。 But for air, the earth would undergo extreme changes in temperature.
But for the laws of motion as a basis, thousands of discoveries and inventions would have been out of the question.
要是没有空气，地球温度就会发生剧变。
如果没有运动定律作为基础，就不可能有成千上万的发现和发明。 第2节 翻译练习8
The positive and negative ions become separated or dissociated.
No electric charges have been observed of smaller magnitude than the charge of protons or electrons.
Foods quick-frozen in liquid nitrogen or carbon dioxide have transformed the way we eat. 正负离子彼此分解或电离。
还没有观察到比质子或电子的电量更小的电荷。